In recent years, a sensor-equipped display device including a sensor (also called “touch panel” in some cases), which detects a contact or an approach, of an object, has been put to practical use. As an example of the sensor, there is known an electrostatic capacitance-type sensor which detects a contact or an approach of a conductor, such as a finger, based on a variation in electrostatic capacitance. A detection electrode and a sensor driving electrode, which constitute such a sensor, are disposed in a display area which displays an image, and are opposed to each other via a dielectric. The detection electrode is electrically connected to a lead line which is located outside the display area.